FAT corrupted

drlucky has the cool Mac to experiment with, I see.  Good to know that there’s a difference, as this can create havoc with a flash drive as well.  With the device connected in MSC mode, a reformat will repair your FAT by the Nuclear Option, starting with a clean slate.

If you start with the Clip+ turned OFF, hold the center button depressed while connecting to force MSC mode manually.

Bob  :smileyvery-happy: